Pitman.



G. E. SMITH.

PITMAN. APPLICATION FILED NOV. 27, 1912.

Patented Feb. 10, 1914.

Attorneys UNITED STATES ra rnntr OFFICE.

GEORGE E. SMITH, DE LOS ANGELES, CALIFORNIA.

PITMAN.

Application filed November 27, 1912.

To all whom it may concern 7 Be it known that I, GEORGE E. SMITH, a citizen of the United States, residing at Los Angeles, in the county of Los Angeles and State of California, have invented a new and useful Pitman, of which the following is a specification.

This invention pertains to improvements in that class of devices, known as pitmen.

The invention has for its object to provide for readily effecting connection between the pitman and crank pin, as well as to effect the expeditious separation of the same, especially in well-drilling apparatus, although the in vention is equally applicable to other machinery embracing elements of analogous nature.

A further object is to provide for assembling and disassembling the pitman with re spect to the crank-pin with facility and accuracy, the same being desired to be performed as rapidly as possible.

A still further object is to carry out these ends in a simple, effective and inexpensive manner.

The invention consists of certain instrumentalities and features, substantially as hereinafter fully disclosed and defined by the claims.

In the accompanying drawing, illustrating the preferred embodiment of my invention wherein it will be understood that various changes and modifications may be made as relate to the details of the construction and arrangement of the parts without departing from the spirit thereof.

Figure 1 is an elevational view of the pitman. Figs. 2 and 3 are similar views there of, certain parts being omitted. Fig. 4 is a sectional and partly broken-away View of the like parts as disclosed in Figs. 2 and 3. Fig. 5 is a detached elevational view of the pitman retaining spring key.

In carrying out my invention, I suitably construct or cast the pitman 1 generally, preferably as disclosed, the same being bodily braced with a web or foraminous intermediate portion 2, which lends to the pitman the requisite strength or rigidity without unnecessarily weighting it, said pitman being adapted to be connected at its upper end to the walking beam, or other like machine-element to be driven from the crankpin, as will be readily appreciated. Said pitman has its lower portion provided with a concaved bearing 3, to form a seat for the Specification of Letters Patent.

Patented Feb. 10, 191

Serial No. 723,902.

crankpin 1 to which the pitman is to be connected; and slidably held between upwardly-extending, lateral guide-forming extensions 4- of said bearing, is a complemental concaved member or yoke 5, whose arc is produced upon lines concentric with those of the hearing or member 3 for obvious reasons, said yoke or member engaging or fitting the upper surface of the wrist or crankpin whose lower surface is engaged by said hearing.

The upper concaved. member or yoke 5. is approximately inverted T-shaped in vertical crosssection as seen in Fig. 4, with the stem of the T extended laterally at its upper portion as at G to engage the guides 4:, the head or cross portion of the T also being adapted to engage said guides as at 7. Said laterally-extended portion of the stem of the T or yoke-member 5 is extended upwardly and has an elongated or oblong slot or opening 8 therein, the greater diameter of which is at right-angles to the vertical plane of said member or yoke, the purpose of which will be apparent later.

A shaft 9, adapted to be suitably actuated by a crank handle 10 is mounted in bearings 11, 11 in common with the pitman casting, said shaft being provided with an eccentric or cam 12 received within the slot or opening 8 of the slidable or movable yoke member 5 for effecting the vertical adjustment of the latter, as in providing for the application of the pitman to the wrist or crankpin or effecting its removal therefrom, as is thought is apparent. Also by means of this arrangement, it is obvious that such connection between the pitman and wrist or crank pin and the disconnection of said pitman therefrom, may be quickly efiected and by the minimum manipulation of parts.

A. rack 13, integral, or in common, with the shaft-bearing 11*, before referred to, provides for the engagement therewith of a tooth or detcnt 1.4 on. the handle or crank 10 operating the shaft 9, for the suitable retention of said handle or crank at its point of adjustment, as in holding said shaft, together with its cam or eccentric, in effective position, with the wrist or crank-pin engaging yoke or member 5, in either position, as disclosed by Figs. 2 and 3 respectively.

In order to provide against the casual detachment of the pitman from the wrist or crank pin, the latter is provided with a peripheral groove or slot 1 1, near its headed end; and with said slot or groove is adapted to be engaged the jaws or arms of a split resilient retaining member, fork or key 15, the latter being adapted to be manually sprung into engagement with the wrist or crank-pin, said slot or opening receiving said jaws or arms of the key as the latter is caused to stride the wrist or crank pin in applying said key as stated. Said key or fork member, it will be observed, is automatic in its retaining action, while it may be readily withdrawn or released by simply exerting a pulling action thereon.

It is considered that the foregoing taken in connection with the accompanying draW- ing, is such a disclosure of my invention as will result in a ready appreciation of its benefits and advantages, it only being necessary to further remark possibly, that it is characterized for extreme simplicity, therefore is inexpensive of manufacture and is eifective for its intended purpose.

WVhat is claimed is:

1. In a pitman the combination of a bearing comprising fixed and movable members, said movable member with an extension projecting therefrom provided with an oblong slot therein, the greater diameter of said slot extending transversely of said extension and at right angles to the line of movement of said movable member, a cam engaging said slot and adapted to actuate said movable member, a cam shaft secured thereto, a handle secured to said cam shaft, and a semi circumferential rack bar concentric to said cam shaft and adapted to engage and hold said cam shaft handle in position.

2. In a pitman the combination of a bearing comprising fixed and movable members,

said movable member formed in the shape of i an inverted T, the stem of said T provided with an oblong slot therein, a shaft, an eccentric mounted thereon and engaging the oblong slot of the said movable member, said shaft extending parallel to the axis of the Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

